ML20053C724

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Seismic Ground Motion Hazard at Zion Nuclear Power Plant Site for Pickard,Lowe & Garrick,Inc
ML20053C724
Person / Time
Site: Dresden, Zion, 05000000
Issue date: 07/02/1982
From: Mcguire R
DAMES & MOORE
To:
Shared Package
ML20049H203 List:
References
NUDOCS 8206020502
Download: ML20053C724 (37)
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.-s4c ::: o -, - n t i i July 2, 1980 i t Pickard, Lowe, and Garrick, Inc. 178!.0 Skypark 30ulevard Irvine, California 92714 Attenticn: Dr. Harold Perla

Dear Sirs:

Transnitted under cover of this letter are three copies of our report, "Seisnic Ground Motian Hacard at zica Nuclear Pcwer Plant Site," for Pickard, Love, and Carrick. This conpletes cur investigatien for the Zicn Nuclear Ptwer Plant site under the terns of our agreenent dated March 2'., 1980. If further investigations are required for this site we will be happy to undertake then. I have enjcyed working with you on this proj ect. If you have any questions or require fur ther informatica, please centact us. Sincerely, DA>cS & MOORE j x me Ro'oin K. McGuire Associate Rft:vb enclosure ec: Dr. 0. A. Cornel.1, M.I.T. Dr. R.P. Kenn2dy, S.M.A.,Inc. )

/ 1 ~ i ~ l TA3LE OF CO:iTE'iTS 11 FIGURE 9: X;:!UAL PRGBA3ILIrl 0F EECZEDriCZ VERSUS PE.E ACCELERATIO:I FOR H?2E ZC::ES USI' G >!IKI VALUES OF b and m,a, max FIGURE 10: NO UAL PRO 3A3ILITY OF EECEEDx;CE ',/ERSUS PE.E ACCELERATIC:i j t0R i:: 3 r .,C.s -f.a A.s;D ,t.,.0 a, t i :...L.. .L, 2 t....,.C,.0,,S .c. u ait, 0 FIGURE 11: CO:TOSITE A:;';UAL PRC3A3ILITi CUR'IE x;D C0}!?0 SITE PE.E .cc.,... _n, _.. . c,. Av w LL.f. N1. ib,.,,, L,..\\,e f. D..11 f. Iw1 1.3 L 4.1 v a s 0 0 _..m..........m 1 J

f TA3LE OF CCNTE:iT Page INTRODUCTION................................................... I SEISMIC HAZAPO '.0 DEL.......................................... 2 SEISMCGENIC ZONES............................................. 4 S E I S MI C ITY P ARAMETERS......................................... 6 { S c. ,7.C G.,0 ..,D.,,O uC,sJ........................... 9 ES.,,. ,0. Oc r . a c. c. v .t..i. RES UI.T S O F X; ALY S IS........................................... 12 S D D'.ARY....................................................... 14 RE FE RE NC E S.................................................... 15 r TA3LE 1: SEISMOGENIC ZCNES MID ASSCCIATED SEISMICITY PARAMETERS TABLE 2: UNCERTAI:i!IES REPORTED FOR ATTE'iUATION EQUATIONS TAELE 3: A' ;UAL PR03A3ILITIES OF EXCEEDM;CE FOR SPECIFIED PEAK ACCELERATICNS {' TABLE '.: PEAK ACCELERATIONS (in ;;) FOR SPECIFIED MCiUAL PR03A3ILITIES OF EXCEEDM;CE FIGURE 1: SEISMICITi MAP OF THE CENTPAL U.S. SHC!iING K'iG!iN EARTH-O - 4.0 (After Nuttli, 1979) QUAKES OF ::. FICURE 2: !JISCONSIN ARCH SEIS'!CGENIC ZONE FIGURE 3: IiISCCNSIN ARCH-MICHIGRI BASIN SEISMCGENIC EONE FIGURE 4: ?aTIO OF PEAK ACCELEPdTION TO SUSTAINED ACCELEPATICN, VERSUS :U.GNITUDE FIGURE 5: COMPARISCN OF ATTENUATION FU';CTIONS FIGURE 6: MC;UAL PR03A3ILITY OF EXCEEDANCE VERSUS PEAK ACCELERATION FOR CESTPAL STA3LE REGION FIGURE 7: MCiUAL PRCBA3ILITY 0F EXCEEDM;CE VERSUS PEAK ACCELERATICN FOR 'iISCONSIN ARCH EOSE FIGURE 3: X;SUA*. PRC3A3ILITY OF EXCEEDM;CE '!ERSUS PEAF. ACCEI.ERATION FOR *.iISCCNSIN ARCH-MICHICA'I 3 A3IN ZONE C

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m.. 1 Increduction The purpose of this study is to make a _ probabilistic assess =ent of the seismic ground cotion hazard at the Zion Nuclear Power Plant, Lake County, Illinoia. The results of this study will be used to calcu-late probabilities of sechanical and structural failure at the facility, and to calculate probabilities of consequences of such failures. 6 A guiding principle in this study is that a "sean-centered" or best estimate analysis should be derived. Further, uncertainty in the best estimate relationship between 3round =otion levels and probabilities of exceedance will be investiga ted by examining uncertainty in the i various assumptions critical to the analysis. To accomplish this, hypotheses which are core conservative and less conservative, in terms of the calculated haza rd, than "b e s t esti= ate" hypotheses, are examined hece. It should be obvious that such an approach would be inappropriate for a detettinistic design procedure. O Consistent with the level of effort available for this study, we rely heavily on the work of others for input to this analysis. The work of TERA Corp (1979) secca rize s a wide range of opinion and expertise on seismicity in the central and eas tern U.S., and the work of Nuttli and Herrmann (1978) provides an analysis of historical seismicity in the central U.S. Prof e ssor Otto N. Nuttli of St. Louis University was retained as a consultant in seiscology for this study; his earthquake catalog (Nutt11, 1979a) (see figure 1) is the source of historical earthquake data used here. The assumptions and analyses conducted 4 remain the responsibility of Da es & Moore. The specific site examined in this study is the Zion Nuclear Power Plant, Lake County, Illinois. The assumptions and hypotheses enamined are appropriate for this site, but may not be for other sites. As an exacple, certain alternate configurations of seiscogenic zones ilC i i i ..* A M h' S d M O J s 4 *? l m

-r=- .~ for the analysis of seLasic La the central U.S. may be appropriate These alternate configurttions C zard at other sites in the central U.S. ha appreciable effect on examined here because they culd have no were not the Zion facility. the calculated seisaic hazard at l L O O U.4 r. J C.*i il *.1 *.;;J J t ij )

{ Seismic Hazard Modal The seiscic hazard model used in this study has been desc ribed elsewhere in detail (Cornell, 1968, 1971; McGuire, 1976), and this description will not be repeated here. Briefly, this model uses sev-eral basic assu=ptions: 1. Zones of po tential future earthquakes are delineated by seis-k sicity and tectonic evidence; the average predicted rates of t occurrence in these zones are accurately estimated by historical occurrences in these zones. 2. The relative frequency of earthquake sagnitudes in seiscogenic truncated exponential distribu-zones can be represented by a tion; and The peak acceleration at the site of interest can be represented 3. as a function of the earthquake cagnitude, the distance between the site and the source of energy release, and the 1ccal soil-conditions. O Given these assumptions, the probabilistic ha:ard analysis consists of mathematically integrating over all possible earthquake cagnitudes and locations, calculating for each =agnitude and location the distribution of peak horizontal acceleration at the site, to evaluate the probability that various levels of acceleration will be exceeded annually. A stan - dard computer program (McGuire,1976) was used for calculations. C $ 9t % s.11: *. 41 ?.10 f 9 9 61 2

_4_ Seistocenic Zones The seismic hazard analysis requires the delineation of seisno-genic :ones, within which earthquake s are considered to be of similar tectonic origin so that future seismic events can be modeled by a single function desc ribing earthquake occurrences in time, space, and I size. The initial seissogenic :ones examined here were those of :utt11 and Herrmann (1978). It became evident that the major contributors to seismic hazard at the Zion site are earthquakes which occur in northern Illincts, and those which occur in the so-called " Central Stable Region of the central U.S. Other seis=ogenic zones such as the New Mad r id zona contribute negligibly to the seismic hazard; they i were included in the analyses for cc=pleteness, using the boundaries and paraceters suggested by :Tuttli and Herr: ann (1973), but their exact delineation and seismicity paraceters are is=aterial for the present study. Three alternate hypothesis were exacined for selsnogenic zones in O the vicinity oe the ette: 1. Central Stable Region. Under this hypothesis, earthquakes which have occurred historically in northern Illinois were assumed to be a part of the Central Stable Region of the central U.S., and no specific seis=ogenic zone was delineated to model the occurrence of earthq uake s in northern Illinois in the future. This hypothesis was assigned a subjective probability of 0.2. 2. h*isconsin Arch zone. Earthquake s in northern Illinois were attributed to a seiscogenic zone bounded to the north by the southern extent of the Wisconsin doce, to the east by the western extent of Silurian rocks, to the south by the northern extent of Pennsylvanian rocks, and to the west by the Mississippi River arch (see Figure 2). The area of this :ene includes the larger historical events which have been reported in northern Illinois and southern Wisconsin. Smaller events reported en the western shore of 1,ake Michigan were attributed to " background seiscicity." This hypo thesis was assigned a subjective probability of 0.5. ,.4 r.m u u m e re n .~ 3. Nisconsin Arch-Michigan 3asin_:one. Earthquakes in northern Illinois were considered to have the same tectonic origin as those in :11chigan, and were attributed to a seiscogenic :one which extends from the ~41scons in Arch to-the F.ichigan Basin (see Figure 3). The eastern limit of this zone was chosen to be longitude 34* 'J ; _ i t s exact location is not ' critical to haza rd analysis at the site because historical seismicity -within the zone is used to estimate the seismic activity rate, as discussed belcu, and historical seismicity in southern !ichigan has a relatively unifor: spatial distribution (see Figure 1). This hypothesis was assigned a subjective probabil- -ity of 0.3. These three hypotheses on - seiscogenic zones in the vicinity of the site we re examined in detail. Results for. each hypothesis, and a 3ayesian ccaposite estinate, are reported below. These three hypotheses represent a range of possible seiscogenic zones in the vicinity of the h site. While other seiscogenic :enes might be hypothesized which would indicate larger (or smaller) seismic hazard at the site, it'is felt that no such zones can be justified on a geological basis, given ' the 'present understanding.of tectonic processes in the central U.S. O w..... m s e n.34,u

Seismicity Parameters For the probabilistic calculation of seismic hazard, several para =e ters describing seismicity are required for each seiscogenic

one.

These paraceters, and the methods used to estimate =ean values and to quantify uncertainty, are discussed below. Seismic Activity Rate. The rate of earthquake occurrence was L estimated for each seiscogenic zone using the historical seismicity l in that zone as repo rted by Nutt11 and Herr = ann (1978). Several cod-ifications were made to the activity rates reported by Nutt11 and 9 Herraann (1978), as fo11cus : i L. Data were corrected to account for the fact that Nut:11 and Herrmann (1978) plotted observed cumulative rates of activity at the center of 0.5 unit magnitude intervals, rather than at the lower end of the interval. The latter procedure is more appropriate for cu=ulative plots of seismic activity. 2. Activity rates were calculated for occurrences of earthquakes with b > 4.0. This decision was based on the observation that earthquakes of smaller magnitude rarely cause structural O damage, even if peak accelerations are high, due t'o the short duration, impuls ive-type ground motions associated with these small events. The method used by Nutt11 and Herrmann. (1978) to account for incomplete repo rting of scall events was reviewed and found to be adequa te. No uncertainty in activity rates was censidered herein, because historical rates of seismic activity are relatively well-determined, even in the central U.S. (McGuire, 1977). The effect of statistical uncertainty in the Richter b-value (discussed in the next pa ragraph) on this mean seismic activity rate is ignored here. This ef fect is judged to be low because the lower bound g=4.0 used here is very close to the average =agnitude of data reported by Nutt11 and Herrmann (1978). Impo rtant in both of these assumptions is the consideration that calculated probabil-ities of exceedance are directly proportional to activity races, and ground motion a plitudes at levels of interest change relatively slowly with respect to probability of exceedance. w

+ s Richter b-value. The Richter b-value describes the slope of ( the log-number versus magnitude relation: () log 10 "I"b) b " *~ where n(s ) is the annual number of earthquakes of bodywave magnitude f b c, and a and b are paraceters fit to seismicity data. Parameter a is related to the seismic activity rate discussed in the previous f 3 paragraph. The average Richter b-value was taken to be 0.92 for all j seiscogenic zones, the value reported by Nuttli and Her-mann (1973). l I - The experts polled in the Tera Corp (1979) study generally felt a single 3 b-value for all zones in the central and eastern U.S. is appropriate. ) The value of 0.92 is typical of numbers offered by the experts (b-values for Modified Mercalli incansity I were converted to b-values for =.o o using the Nut:11 and Herrmann (1973) relation I = 2 g - 3.5). Uncertainty in the Richter b-value was modeled by changing the

ean value by + 157..

This is a typical range for one standard deviation O-c.ntral and or statistical uncertainty for calculated b-values in the e eastern U.S. Probabilities associated vith these alternate values are discussed in conjunction with maximum magnitude belas. Maximun Magnitude. The maximus bodv-wave cagnitude m. of o,cax each hypothesited seissagenic zone was assigned using the subjective judgment of the seismological consultant to the project. For each hypothesized :one the maximum historical earthquake had an estinated was chosen to be 5.8, with a b,f 3.3. The best estimate of =b y e range of 5.5 to 6.2. A double-triangular probability distribution was chosen to represent uncertaintv in a over this range. For pur-b,=ax poses of computation and presentation, the double triangular distribution discrete values of =bm (5.6, 5.8, and 6.0) was representad by three with associated probabilities (0.23, 0.44, and 0.28) respectively). s. u.. u n r,wo n.1 A

i. I t ' wa s felt by the-seis=ological consultant that-there is soce negative correlation between b-values and values of =, That is, o,=ax it was. felt that low values of b are associated with relatively high values-of m and vice versa. No attempt was made to develop a by sophisticated odel of this correlation; rather, we made the si=pli-fying assumption that low b-values (the =ean minus 15::, as discussed above) are perfectly. correlated with high values of g (6.0) and I similarly for high b-values. This assumption does not affect the i "best estimate" curves to be produced by this study; it does produce a 'dder range of hazard curves resulting frem parameter uncertainty, I than if less-than perfect negative correlation between b and =b,=ax t r were modeled. Since the predcainant spread of hatard curves results trom uncertainty in seis=ogenic :ones rather than frec uncertainty 1 in seismicity parameters (as will be demonstrated below), this simpli-l l fying assuspeion is of sinor consequence and is therefo re -jud ged appropriate. a h Table 1 presents the three hypotheses on seismogenic zones and their ascociated seismicity parameters. For the Wisconsin Arch :ene i the background seisnicity contributed =arginally to the seismic hazard 1 -4 (e.g. it contributed 25% of the probability at the 10 annual probabil-f ity level). Hence uncertainty in the Richter b-value and in m. was ~' D,OaX not considered for background seismicity. O me., u n n :., u o r a h

_m _9 ~ i Istination of Seismic Ground Motion Es ti=a t es of peak s ing le-component horizontal ground acceleration for an earthquake of given magnitude =b and epicentral distance 6 were l made following the theory of ::ut t11 (1979b) for higher mode surface theory estimates a sustained level of acceleration corres-l waves. This ponding to the third highest peak in the acceleration time history, for l earthquakes of several cagnitudes. An equation was fit to this theory to y allow esti=ation of sustained acceleration a, for a continuous range of i l magnitudes and distances: i < 10km 0.384 exp(-0.427 exp(.444c ) + 1.098m ) 1 b = a, (2) k -5/6 exp(.0427 4 exp(.444g) + 1.098=.,)4 > 10km 3.98 A l a, = I These equations are appropriate for estinating sustained acceleration at sites underlain by cedium to hard soils, and thus are appropriate I j i for the Zion site. To estimate peak acceleration, the ratio of peak te s==teiaea.eccetera=1o= was aiotted ve==ue =esaicuae cor the aeta. O used by ::ut:11 (1979b). Figure 4 shows this plot. It,i s logical this ratio should be larger for smaller =agnitudes (sc < 5.0) than I that D-because of the shorter duration -(and for larger =agnitudes ( b > 6.0), l core " spiked" nature) of ground =o tions during small magnitude earth-l l quakes. In fact the data of Figure 4 indicate an average ratio of 1.75 i l for g <_ 5.0, and 1.37 for ab > 6.0. J For calculations of seismic hazard in this study we use a single l value of 1.37 for all mannitudes, based on the notion that a reduction l in peak acceleration for s=all magnitudes is appropriate. This follows from the obse rva tion that da= age to structural and nechanical systems f [ requires several cycles of input motion at a given amplitude level, l rather than a single high frequency acceleration pulse. More justifica- -ion and explanation of this procedure is offered by structural engineers I involved in this project (Structural Mechanics Assoc., 1980), t O 1 s,.uw a a r.s o t.r e.t I

I There is a second modification to Nuttli's theory required to estimate peak acceleration. Nuttli's wo rk was based on,.tnd calibratec. to, the larger of the two horizontal ecmponents, ihereas we wish to. I estimate the peak ' ho ri:ontal acceleration in a randomly-o rien ted direction. The appropriate f actor (mean ratio of the peak of a randomly-chosen hori:ontal component, to the large r of the two horizontal components) is 0.9, based on an analysis of the data used by Nuttli. L i Combining these two effects into a single factor of 1.23 (1.37 l times 0.9), we e s tica te the peak sustained-based acceleration a as: ps I k 1.23a (3) a = ps s i i This acceleration is plotted as a function of distance for several values i of g in Fi;;ure 5. For comparison, we also show a peak instru= ental acceleration a estimated using a peak-to-sustained-acceleration ratio j of 1.75 for m 5.0, a ratio of 1.37 for ab> 6.0, and a linear b interpolation for 5.0 < m* < 6.0. Mathematically, 1 O l 1.75 a m <5.0 s b (1.7 5 - 0.33(m -5)] a 5. 0 < m. < 6.0 (4) a = b s o-pi l 1.37 a 6.0 < m s b l Several alternate equations were examined for esticating peak horizontal acceleration at soil sites in the central U.S. The relation i reported by Nutt11 and herrmann (1978): 1.2m b -L.02 6.92 e a 6 > 15km (5)

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is appropriate for esti=ating peak horizontal vector acceleration. ?!ultiplication by the factor 0.7, based on the :;uttli (1979b) data set O ca=d coneirmed i=4egeedent17 bz ser =enn) sives en eet1= ate oe geax horizontal component acceleration. The modified relationship is plotted in Figure 5 and gives values almost identical to the =odified Nutt11 theory. Use of equation 5 in the hazard analysis gives results which are virtually identical to those obtained using !!ut tli's codified theory; h hence equation 5 is not exacined further in this study. A third cethod of estimating peak horizontal acceleration at soil sites in the central U.S. was examined: that of TE?.A Corp (1979). Their equation (based on intensity attenuation and acceleration-intensity correlations) is: 0.985 R.501 exo(1.14c .0026R) (6) a = p,t b where R is an unspecified source-to-site distance, taken here to be epicentral distance. Estimates based on this equa tio n are shown in Figure 5, and ind ic a te a cuch lower decrease of acceleration with, distance than the other two methods examined. The effects of this alternate equa tion on calculated seismic hazard are exanined belov. For calculation of seismic hazard, a legnor:al distribution of acceleration about the =ean value was assuced, with a value of CT of 0.6, corresponding to a factor of 1.8 uncertainty in the ng estimate. This distribution is widely used to represent uncertainty in ground =o tion estinates; the uncertainty codeled is typical of the scatter exhibited by strong :otion data sets, as shcun in Table 2, when the data are restricted to a specific area such as the westera U.S. Some of the studies listed in Table 2 (Shannon and Wilson, Inc., and Agbabian Assoc.,1979, and Trifunac,1976) are heavily biased by data frc= the San Fernando earthquake; others (>!cGuire, 1974, 1978) are not. When data from world-wide locations are used in the analysis, larger values of uncertainty are obtained because of different =ean attenuations. In this study we prefer to use an uncertainty typical of a specific geographic area, and exacine the effects of uncertainty in the mean attenuation h directly by examining several attenuation functions. ~ ~ ~ ~ ~ ~ * ~ - "****'*****e** J

2esults of Analvsis Figures 6,7, and 3 show the calculated annual probability of c.secedance ve rsua peak acceleration for the three hypothesi:ed seis-nogenic zones listed in Table 1, calculated using the modified Nuttli 1 estimates of peak acceleration. Uncertainty in b-value and in m. o,=ax contributes socevhat to uncertainty in the calculated hazard. The results are such mo re sensitive to the seistogenic zone which is con-( sidered repr esentative of the 4 source of earthquakes af fecting the Zion site. This is illustrated in Figure 9, which cocpares the curves for the three zones, calculated vi:h the mean values of b and m To illustrate the dependence of calcula:ed haza rd o'n the =e: hod k i used to estiente peak acceleration, Figure 10 shows a comparison of the hazard curves of Figure 9 (based on the Nut:li =ethod, equation 3) with hazard curves calculated using the TERA (1979) method (ecuation 6). j 1 The results can be explained in terms of the different esti stes of peak acceleration shown in Figure 5. If the predcnonant earthcuake threat is frca events in the distance range 40 to 100 k: (e.g. fros the Uisconsin Arch :one), the two attenuations indicate abcu: the same accelerations s y (Figure 5) and produce abou: :he sa=e hazard curves. Ii' events closer than 40 km contribute significantly to the seis:ic hazard (e.g. in the case of the Central" Stable Regi:n and the Wisconsin Arch - Michigan Basin j

one), :b'e TERA (1979) at:enuation indicates lower accelerations and 1

produces lover hazard curves. 1 i In general, the va riati:n in ha za rd resulting from the use of p c1:'ernate estimates of peak a:: ele ra tion is vi:hin the variation r e-- sul e'l ag free different hypc:heses on seisecgenic zones. Also, the a .use of site intensities as an intermediate s:ep in predicting peak acceleration (as is done-ih the TERA ce: hod) can lead to an unrealis-1 tice.lly low attacuat16n of ac;neration with dis:ance (see Cornell et al, l'979);..this probably con:ritu:es :o the low attenuation exhibited by the J s TEFi *(1979) cu:ves (Figure 5'. Thase c.cnsiders: ions lead us to reject w L: ', for-al applic.ttion of the TIEA J79) curves and use results based solely - on the Nuttli esti=ates of at:sWa:icn. J [~ 3-j si EY l 3 l .s .'h D.T..au M !*, At O O M G s ~, Y l >..n .j, t4',.- -.'.s.- 'sI y((

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,. - - - - - - - - - - - - - ' " - - - ' - ' ' - ' - ~ ' - - - - ' ' ~ '

The annual probability of exceedance for each of the seismogenic zones is shown in Table 3, and each of the combinations of values for b and nh, max (h for several levels of peak acceleration. Also shown is a Bayesian or compo-site estimate of the probability of excecdance, thich is the best estimate of the annual probability of exceedance for the indicated peak accelerations at the Zion site. Prcbabilities are calculated for peak accelerations up to 1.5 g; while the methodology indicates that these high accelerations may be exceeded, it should be recognized that dynamic soil properties might limit peak accelerations during strong earthquakes. Unfortunately there is no sim-ple method of calculating such limits, nor do empirical data suggest anp lirait s. The 1979 Imperial Valley earthquake, for example, prcduced a strong motion record at a deep alluvium site with a peak acceleration of 1.7 g (in the vertical direc: ion). Bayesian or composite estimates of peak accelerations for specific probability levels are obtained by computing the weighted average of accele-rations for each hypothesis on seismogenic zones and scianicity paraceters. Table 4 summarizes these results for the Zion site. Figure 11 shows the composite annual probability curve and the composite peak acceleration curve. The applicati'n of these best esticate hazard curves should dictate the choice of which curve to use. For calculatbn of structural and mechanical reliability under seistic loading, where probabilities of occurrence of various levels of acceleration are convolved with probabilities of darage given those accelerations, the composite annual probability curve is the appropriate one to use. O o n ra r > c c.m a n c

n _%._narv L'e present here a seis=ic hazard analysis for peak ground accelera-O

ion at the Zion nuclear powe r plant site.

The analysis is highly dependent on :he spatial extent of any hypothesized seismic source which produces earthquakes in the vicinity of the site. This is illus-trated by the sensitivity of calculated seismic hazard 'o the three hypothesized seiscogenic zones examined here. The analysis is less sensitive to uncer:ainties in paraceters defining seiscicity in the seiscogenic zones. The nos: appropriate attenuation function which esticates peak acceleration as a func:fon of earthquake =agnitude and distance is obtained frca a codification of the ::ut:li (1979b) theery for higher code surface waves. An alternate fune: ion proposed by Tera Corp (1979) influences the seismic hazard for each seiscogenic zone hypo the sis, but in a compensating canner so that the weighted average hazard curve would not be changed greatly by the use cf this alternative antanuation f unc t io n. O j h 'O II8-4 ?.S dd (5 O ici O(I 9 O ~~,.-,--m._ w m~mm- ~.. ~ ~ - -.

4 REFERENCES C Ca:pbell, K.U. (1980), "Preli=ir.arr Evaluation of Near Source Attenua-tion of Peak Acceleration in the United States," Abstract, Eastern Section Notes, SSA, April, p. 16.

Cornell, C.A. (1968), " Engineering Seismic Risk Analysis," Bull. Seis.

A Soc. Am. 58, 1383-1606.

Cornell, C.A.

(1971), "Probabilistic Analysis of Da age to Structures under Seis=le Load," Chapter 27 in Dyna =ic Waves in Civil En-gineering, D.A.

Howells, I.P.

Haigh, and C. Taylor, Editors, Wiley Interscience, London, 473-488.

Cornell, C.A.,

H. Banon, and A.F. Shakal (1979), "Seis=ic Motion and r Response Prediction Altarnatives," Earthquake Eng. and'Struct. Dyn., Vol 7, pp 295-315.

Donovan, N.C.,

(1973) Earthquake hazards for buildings, in 3uilding practices for disaster citigation: Natl. Eur. Standards Building Sci. Series 46, p. 62-111.

Donovan, N.C.

(1974) A statistical evaluation of strong :otion data including the February 9, 1971, San Fernanco earthquake: World Conf. Earthquake Eng., 5th Ro=e 1973, Proc., v. 1, p. 1252-1261. -

Esteva, L.,

and Villaverde, R., (1974) Seismic risk, design spectra, and structural reliability: World Conf. Earthquake Eng., 5th, Rome 1973, Proc., v. 2, p. 2386-2396.

McGuire, R.K., (1974).

Seismic structural response risk analysis, incorporating peak response regressions on earthquake =agnitude and distance: Massachusetts Inst. Technology, Dept. Civil Eng., Research Rept. R74-51, p. 371.

McGuire, R.K.

(1976), " Fortran cocputer Program for Seismic Risk Analysis," U.S. Geol. Sury., Open-File Rept. 76-67. McGuire, R.K. (1977), " Effects of Uncertainty in Seiscicity on Esticates of Seissic Hazard for the East Coast of the United States," Sull. Seis. Soc. Am., Vol. 67, No. 3, June, pp 827-648.

McGuire, R.K.,

(1978a) " Seismic Ground Motion Parameter Relations," Joun. Geotech. Eng. Div., A.S.C.E., April, pp 481-490.

McGuire, R.K., (197Sb). "A Si ple Model for Esticating Fourier A=plitude Spectra of Horizontal Ground Acceleration," Sull. Sais. Soc.

A=., l Vol 68, No 3, June, pp S03-822. O eu.,essmovac r -m_._

Nuttli, O.W.

(1979a), "Seis=icity of the Central United States," Geol. Soc. of A=, Rev. in Eng. Geol., Vol IV, pp 67-93. O Nuttii, 0.W. (1979b), "The Relation of Sustained Maximu Ground Accelera-tion and Velocity to Earthquake Intensity and Magnitude, Report 15, Misc. Paper S-7-1, U.S. Army Eng. Waterways Exp.

Station, Vicksburg.

g

Nuttli, 0.W.,

and R.B. Herr = ann (1978), " Credible Earthquakes for the Central United States," Report 12, } Esc. Paper S-73-1, U.S. Army Eng. Waterways Exp. Station, Vicksburg. I Patwardha=, A., K.

Sadigh, I.M.

Idriss, and R. Youngs (1973), "Attenua-I l. tion of Strong Grcund Motion--Ef fect of Site Conditions, Transcis-sion Path Characteristics, and Fcc 1 Depths," in preparation. See l 1.M. Idriss, " Characteristics of Earthquake Grcund Motions," paper 1 presented at ASCE Specialty Conference on Earthquake Engineering and Soil Dyna =ics, Pasadena, June 1978. Shannon and Wilson, Inc., and Agbabian Assoc. (1979). " Statistical Analysis of Eartaquake Ground Motion Parameters," U.S.N.R.C., NUREC/CR-ll73, Dec. Structural Mechanics Assoc. (1980), "Co ndi t io nal Probabili:1es of Seismicolly-Induced Failures for Structures and Cocponents for the Zion Nuclear Generating Station," report prepared for Pickard, Love, and Carrick, Inc. TERA Corp (1979), "Saissic Hazard Analysic-Solicitation of Expert Opinion, study funded by Lawrence Livermore Lab., Aug.

Trifunac, M.D.,

(1976) " Preliminary Analysis of the Peaks of Strong Earthquake Ground Motion-Dependence of Peaks en Earthquake Mag-nitude, Epicentral Distance, and Recording Site Conditions," Bull. Seis. Soc. As., Vol 66, No 1, Feb., p 189-219. + 0 -m r.m s a ew o.m n

TA31.E 1 SEIS 10GE iIC ZC::ES A';D ASSOCIATED SEIS:tICI~~i P.t"LU!ETERS O Seiscogenic Subjective Activity Richter =. Conditional p l Zone (s) Probability Rate b-value Probability * (Events per year with 4 g >,,4.0) Central Stable -3* Region 0.2 2.66x10 0.78 6.0 0.28 O.92 1 5.3 i 0.14 l 1.06 t 5.6 O.28 {- c 0.78 6.0 0.28 Wisconsin Arch 0.0695 0.92 I 5.8 l 0.14 1.06 1 5.6 i 0.28 I 0.5 i

Background

-3* Seis=icity 2.00x10 0.92 5.0

1. 0 b'isconsin Arch-0.78 6.0 0.28 0.3 0.0895 0.92 1

5.3 1 0.14 4 d,ichigan Basin 1.06 1 5.6 1 0.23 1

  • annual rate per 10.000 km.

+ conditional probability of the values shown for b and 4,=ax, given the seis=ogenic :one. o O 3 =.-r=-em,r- -. es.-y y, ~ ~ ~, _, "*'{ ' y y]* * ] g < m_ve,,, f. ~ y pgw,og.gg,,

TA3LE 2 h UNCERTAINTIES RIPORTED FOR ATTENUATIO:! EQUATIONS Reference Data Base a Canpbell (1980) Western U.S. 0.60 Cornell et al (1979) Western U.S. 0.57 Dcnovan (1973) World-wide 0.84 Donovan (1974) San Fernando 0.481 Donovan (1974) Wo rld-wide 0.707 Esteva & Villaverde (1974) Western U.S. 0.64 McGuire (1974) Western U.S. 0.51 McGuire (1978a) Western U.S. 0.62 Paceardhan et al (1978) California, Japan, 0.58 Nicaragua, India (shallow focus) Shannon and Wilsen, Inc., and Agbabian Assoc. (19 79) Western U.S. 0.573 Trifunac (19 76) Wes te rn U. S. 0.60*

  • Calculated using procedure discussed in McGuire (1978b).

O Gree a s em +e mee,,e e # .,m. ,,y

O O O;- ~1'ABI.E 3 M3HUAL PROBAHILITIES OF EXCEEDANCE FOR SPECIFIED PEAK ACCELERATIONS Seismogenic h m Proha-Peak Acceleratlo:1,_( g)_ 7.one hl11ty* 0.1 0.15 0.2 0.25 0.3 0.4 0.5 Cen t.ra l .78 6.0 .056 .33x10~ .14x10~ .70x10- * ~ ' ' ~ .53x10~ . 40 x 10 .25x10 .lix10 ./Sx10 .25x10 '_.1.5_x 10~.6Jx10_ j0x 10_5, ~3 ~ f, .92 5.8 .088 _. 2 3_x 10 d2x.10_ _ i g .36x10 .16x10 1.06 5.6 .056 .18x10 .66x10 31x10 .16x10 . 9 3x 10 .78 6.0 . 140 .32x10 .91x10 33x10 .14x10 .66x10~ .18x10' . 60 x 10 ~ ' ' -3 ~' ~ ~ -5 -5 -5 tlisconsin .92 5.8 .220 .20x10~ .57x10 ^ 21x10 ^ .89x10 .43x10 .12x10 .42x10 1.06 5.6 . 140 .15x10 ~ ~' -5 -6 ^h ~ .42x10 ^ 16x10 ^ .72x10 .35x10 .tix10 ,33xyg ~ ' ' ~ ~' Visconsin .78 6.0 .084 .10 x 10~ .42x10~ 2lx10~ .12x10' .75x10 .33x10 ^ .17x10 ~ ' ' ~' ~' -I ^ # 'I' ~ ~ .29x10~ 14 x 1,0I,_,, .78x10 .46x10 .19x10 .90x10 .92 5.8 .132 . 74 x l_0 1.06 5.6 .084 .59x10 .22x10~ 10x10~ .53x10 .30x10 .Ilx10 ^ .50x10~ ~3 ~ ~ ~ 1 ci nan Composite Bayeslan Est imate .39x10~ .14x10' 66x10~ ' ~ .20x10 .82x!0 .39x10~ .'15x10

  • Calculated as the product of tiie zone prohahtlity and the b-m, probability, Tahic 1.

9 w -o l .n-

O O O TABLE 3 (Continued) ANNUAL PROBABILITIES OF EXCEEDANCE FOR SPECIFIED PEAK ACCELERATIONS f. Acceleration, W Proba-Seismogenic b >53X bility* 0.6 0.7 0.8 l 0.9 Zone -5 -5 -5 -6 Central .78 6.0 .056 .32x10 .19x10 .12x10 .77x10 -5 -6 -6 -6. .92 5.8 .088 .16x10 .90x10 .53x10 .33x10 Stable -6 -6 -6 -6 1.06 5.6 .056 .81x10 .43x10 .24x10 .14x10 -6 -7 -7 .78 6.0 .140 .23x10 ,97xyg .44x10- .21x10 ~0 .92 5.8 .220 .16x10 .72x10 .34x10 .17. " 0 Ulsconsin Arch -6 1.06 5.6 .140 .15x10 .68x10' .32x10" .16x. -5 -5 -5 -5 Wisconsin .78 6.0 .084 .95x10 .56x10 .35x10 .22x10 -5 -5 -5 -6 .92 5.8 .132 .47x10 .27x10 .16x10 .95x10 ch - clichi gan -5 -5 -6 -6 Basin 1.06 5.6 .084 .25x10 .13x10 .72x10 .42x10 -5 -5 -6 .43x10 Composite Bayesian Estimate .21x10 .12x10 .71 10 i .m

TATLE 3 (Continued) ANNUAL PROBABILITIES OF EXCCEDANCE FOR SPECIFIED PEAR ACCELERATIONS p Peak Acceleration (g)

  • E" o, max bility 1.0 1.1 1.2 1.3 1.4 1.5

-6 -6 -6 -6 -6 .78 6.0 .056 .51x10 .35x10 .24x10 .17 10 .12x10 .88x10- -6 -6 -7 -7 -7 -7 a c .92 5.8 .088 .21x10 33 yg .90x10 .61x10 .43x10 .30x10 "U .53x10' .34x10- .22x10- .15x10- .10x10-1.06 5.6 .056 .85x10 -0 -0 -0 .78 6.0 .140 .Ilx10' .59x10- .33x10 .19x10 .Ilx10 .69x10- -0 -8 -9 Wisconsin .92 5.8 .220 .88x10- .48x10' .27x10 .16x10 .95x10- .58x10 I ^ #'I' . 4 7x 10' .26x10- .15x10 .93x10 .57x10 -8 ~9 -9 l.06 5.6 .140 .84x10 -5 -5 -6 -6 -6 Wisconsin .78 6.0 .084 .ISx10 .10x10 .69x10 .49x10 .3Sx10 .25x10 -6 -6 -6 -6 -6 .92 5.8 .132 .60x10 .39x10 .26x10 .18x10 .12x10 .86x10 Michigan -6 -6 -6 -7 Basin 1.06 5.6 .084 .25x10 .16x10 .10x10 .65x10- .44x10- .30x10 mp sit -6 -6 -6 -7 -7 -7 .28x10 .19x10 .13x10 .87x10 .61x10 .43x10 Bayesian Estimate

  • Calculated as the product of the zone probability and the b-m Probability, Table 1 b, max 4

O O ~ ~~ ~~~ T G

TABLE 4 PEAK ACCELERATIONS (in g) FOR SPECIFIED ANNUAL PROBAUILITIES OF EXCEEDANCE I Seismogenic Peak Acceleration (g) with Zone b Probability

  • Annual Probability of

~4 -5 -6 10-10 10 10 Central .78 6.0 .056 .056 .17 .42 .84 Stable .92 5.8 .088 .048 .15 .34 .68 Renion 1.06 5.6 .056 .044 .13 .29 .57 Wisconsin .78 6.0 .140 .064 .15 .27 .45 Arch .92 5.8 .220 .055 .13 .24 .42 1.06 5.6 .140 .049 .11 .23 .40 hconsin .78 6.0 .084 .10 .27 .59 1.10 .92 5.8 .132 .086 .23 .49 .89 Michigan 1.06 5.6 .084 .078 .20 .41 .74 Basin Composite Bayesian Estimate .064 .16 .34 .62

  • Calculated as the product of the zone probability and the b-m Probability, Table 1.

b e 2-. o n p. y

SC .4 g L

  • a

.g R g '. / _ >24 ??. m 53 .s + s 4"k* 7 j s j C. (. gA.x._- .r ^ 9 f,% '.. ('. i y fI t o. - / ^ .+. s i V .' f l .N w <e,,[ .. ~.- ) C \\. ~ s ..f _ A - 'w. s g/.,* ' " Q. ~. - /uf, I + -d } \\ _} a j ? ..N. D a N N r. '~. , r. 1 .t l'- 3 .- i.. g . y- ..n,..- I w. i t.; f ? , 'i.

  • J fw'

.i ' y.,

  • f p

y.6.. b y :. L . n f,- / vig, A-- .s .6,,.. -- 2 1 }.. I s u v .t ,I.,* (j ,:=. .'Y f. j =- a y p I %w. e-

. /.,, a I

IC a eg 33 t ) \\. A C = m, = 4 ? ( f a *..C = m, s ' 3 4 sc=,.s3 a "" / O 7."l = mg s 73 ~ 7 / I A, 1 O.

Ct l.

p V r ^y-v, w r,sj%'t c:3 cm 2;::m ? zs _ 5 D 25 't l 1 i l l FIGURE I SElSMICITY MAP OF THE CENTRAL U.S. SHOWING XNOWN EARTHQUAKES OF M a4.0 (AFTER NUTTL1,19791 b ONMNN b M NN - - - em ..--m+. a-. _w_

0 0 8@ e4 0 900 88 92 l l k O, 0 - 47 ~ C _5 4 WISCONSIN MINNESOTA MICHIGAN - 43 ( i / V N/ - 8 SITE ( x-x - s O /,< ICWA- - 410 ILLINCIS INCIANA CHIO l i I I l' I Figure 2 WISCONSIN ARCH SEtSMOGENIC ZONE o ~.,n . m. ^

99_a 90 880 8 60 a40 ~ k 47* O -~ k, a 45 WISCCNSIN V k / ..fiNNESOTA RJ.g - 4 3'3 kf / S' A "Q : ' NN

cwa

/ / O \\ u .s .s s _4 ; o ILUNCIS INDIANA CHIO / s i I I I i l l ~ s Figure 3 WISCONSIN ARCH-MICHIGAN BASIN SEISMCGENIC ZONE O t oa..-- n 3 = n o

l a..n. - (D W -Jo>-o LA.. i L

  • =3-O H<

C: W _.J W u' 09*5-o- LARGE NUMBER OF g DATA PCINTS. RCM = SAN. ERNANDO i EARTHCUAKE NOT SHOWN coa2-co s 3 c-W JI.5-y W' c a x r W c, I i i i 4.0 5.0 6.0 i\\1b l Figure 4 RATIO OF EAK ACCELERATION TO SUSTAINED-ACCELERATION, VERSUS MAGNITUDE l n n ~. a n - n. a n W &W wag % 9We,W&H ^m'99 -= 4 w M b

O n 9 r l I AVERAGE PEAK ACCELERATION, 9 6 0 .o O b~ ~ Y / / / h l l l / l l j ,/ / / i cn v / j f 3 d [i, h, / O / / / / x x //,f 1 x / ,. u = c o u i bb / 3 / 5 P,,, !2 a. N 1> 4 / ". / / b / ss 1 k *,r , f"h s -g n 5 5, $ 0 l g& $E / U g,x t i za es c c ,/ // / > 01 o o. r /

iy ^ g

-1 a / f a g < r, I'3 c

  1. U I.! i d 5

/ "a z h // / o n g l:, / // @<Cy C 5 / // ~_ f r! : i .$,d 9 C z / / / l O M / a- / // ~p y$ o,/ _g i o / / / 1 u., c, s., O ,f / ?A ' u $ l5. # / 2 M [' i k a .= 8. /- 1 M.C G a* 2ma n - in d [ 2 e ,s 4 r

O s t C ~3 10 k. b lmS, mar w

0.78i 6.0 i S

e ! O.9 2 ! 5.3 i ! !.06 ! 5.5 j u -4 u 10 oXW u.o >-b C< ao Cr* c_ _.1<a 5 10 _ -5 to-6 e 0.04 0.10 0.2 0.3 0.40.5 PEAK ACCELERATiCN, g C FIGURE 6 s 7 I ANNUAL PROSASILIT'r OF EXCEEDANCE VERSUS PEAK ACCELERATICiN FOR CENTRAL STAELE REGION. a.~..numma w.= -o w,.,,s.em m ee.oe. een - =~w**~' ' * ~ ~ ' = * * * = * ~ ~ "

m n m 7 1 6 i I ANNUAL PROBADILITY OF EXCEEDANCE n f4 y b, A' @ ~ 8 6 ~ h' O o 9 d a O1 I Or fI't) ~ / !U[ L {9 =' m di 9S O .O nn '? k o b# 'T o m / / as 9 y 1 o ~; i. b, ' q 1 ru M }_* B h () O to Oo W ~ ol? O. np g ir; .~ 2E~ P y j '4 f -s

y,s

.o ~ ~ s b Ut y r . It1 N ~A) O U) ~' C f3 M 0 t 0 G I I '2 t T 7

h b O .s m 10> h ANNUAL PROUADILITY OF EXCEEDANCE O OD1 b I-~ Z fil Z o O, O, o, I

  • u C e

by O Gn un E* ts* O --- t r' 4 On Z ;0 O 1 4 m W"j 2! X o

L o

p - 1 -O (n -{ C O O -< ~0 O O IU I4 o l,, p Di ~0 m 2n u re b a b O _j 'o ( O" ~ [P'P $ [il i xo

- 13 O w ~

4' O) 10 0) Ib so o_ 3 O iri 9 (O

0) y' 81 oi 0.

.L

0) (s) O d.

5 'f l M} .. z. <n UJ C a

r. ca l

) 01 I E 3 ) a } O I4 0 2 {Q 9 ,2

6:

l i

O 0 10'3 Fw WISCONSIN ARCH-MICHIGAN 2ASIN ZCNE too2< (' Q Ld io', to o X La E!4TPJL u. STASLE REG lCP1 O t- =1 m<a oc-c- p) \\ J<a 5 10 -5 WISCCNSIN ARCH ZCNE l ( l l 1 l 10-6 1 0.04 0.10 0.2 0.30.40.5 l PEAK ACCELERATICN, g l l FIGURE 9 \\ l ANNUAL PROSA5!LITY CF EXCEEDANCE VERSUS PEAK l h ACCELERATION FOR THREE ZONES USING MEAN VALUES CF b AND mb, max l D A M et S 8 M OC M t3 l l -~--

P ~ MCDIFIED NU i : U ATTENUATICN TERA CI 9T9) ATTENUATICN I o - \\\\\\ \\\\\\ l' \\\\ WISCCNSIN ARCH-g M!CHIGAN 5ASIN ZCNE o 2 e \\ -4 w 10 o XU .t 1.L. } o \\ =! \\ c1 cso 4 b.- E a< n '{ ~ -5 y io \\ k CENTRAL STAELE REGION: \\\\\\ \\ \\\\ WISCCNSIN 6 ARCH ZCNE \\ \\ \\ .\\. i 10'* 0.04 0.10

0. 2.

0.30.40.5 PEAK ACCELERATICN, g FIGURE I O ANNUAL PRCSASILITY OF EXCEEDANCE VERSUS PEAX ACCELERATICN FOR THREE ZONES AND TWO ATTENUATiCN FUNCTIONS aa.,, nywu_ gpgy I

A ~3 10 ( l - C0tAPOSITE ANNUAL -4

A PROBABILITY CURVE Io W

O ?,*,'. z Q Ww ( O X W u. O -5 b 10 =' a3 COMPOSITE PEAK O ACCELERATION ( E CURVE -.s< Dz z 4 -G _ io t l l l \\ 1 10-7 _1 i j o.04 0.1 0.2 0.30.40.5 1.0 PEAK ACCELERATION, g FIGURE I i l COMPOSITE ANNUAL PROSABILITY CURVE AND COMPOSITE PEAK ACCELERATION CURVE FOR THE ZION SITE 1 O d4 M s G B M O O R un - ~ ~ - - - . - _}}

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